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Process Efficiency (process + efficiency)
Selected AbstractsShort Chemoenzymatic Azide-Free Synthesis of Oseltamivir (Tamiflu): Approaching the Potential for Process EfficiencyADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1 2010Lukas Werner Abstract A short chemoenzymatic and azide-free synthesis of oseltamivir was attained with the key steps consisting of a one-pot Dauben,Michno oxidative transposition and amination and a reductive transposition of an acrylate. [source] The role of organizational capabilities in cleaner technology adoption: an analysis of the response of the pharmaceutical manufacturing sector in Ireland to IPC licensing regulationsENVIRONMENTAL POLICY AND GOVERNANCE, Issue 6 2006Rachel M. Hilliard Abstract In introducing integrated pollution control licensing, regulators hope to achieve economic advantages as well as environmental benefits. The licensing is used as a vehicle for encouraging firms to adopt cleaner technology, potentially allowing firms to achieve economic advantages through process efficiencies and reduced environmental control costs. In Ireland, the regulatory approach has been to require firms to make managerial changes in the belief that this is a necessary precursor to the take-up of new technology. This paper examines how the pharmaceutical manufacturing sector has responded to environmental regulations that require cleaner technology adoption and managerial changes. Quantitative indicators are developed using data reported to the Irish Environmental Protection Agency. Analysis shows that firms were differentially able to implement both cleaner technology and the mandated managerial processes. The implications for policy are that regulatory instruments designed to stimulate cleaner technology may not be sufficient to promote change in firms, given that the influence of these instruments is mediated by the role of firm-specific, experience-based organizational capabilities. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment. [source] Review: Microscale methods for high-throughput chromatography development in the pharmaceutical industryJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2009Sunil Chhatre Abstract Demands within the pharmaceutical sector to cut costs and improve process efficiencies have grown considerably in recent years. Major challenges exist for companies trying to establish financially viable and robust manufacturing processes for increasingly complex therapeutics. These issues have driven the investigation of miniaturised process-design techniques by which to identify suitable operating conditions using small volumes of feed material typical of that available in the early stages of bioprocess development. Such techniques are especially valuable for the optimisation of chromatographic separations, which often represent a significant percentage of manufacturing costs and hence for which there is a pressing need to determine the best operating policies. Several methods employing microlitre volumes of sample and resin have been explored recently, which are aimed at the high-throughput and cost-effective exploration of the design space for chromatographic separations. This methodology paper reviews these microscale approaches and describes how they work, gives examples of their application, discusses their advantages and disadvantages and provides a comparative assessment of the different methods, along with a summary of the challenges that remain to be overcome in relation to these techniques. Copyright © 2009 Society of Chemical Industry [source] Impact of environmental conditions on the performance of cartonboard skilletsPACKAGING TECHNOLOGY AND SCIENCE, Issue 5 2005C. Berry Abstract This paper discusses the importance of understanding machine,material interaction for achieving high process efficiencies. In the area of cartoning, the performance of cartonboard and hence the efficacy of the machine,material interactions can be significantly altered by changes in environmental conditions. In this paper, the process of carton conversion is dealt with and its performance during creasing, folding and subsequent erection is considered. An experimental programme was created to investigate the effect of moisture on the carton performance and in particular the important attribute of ,spring back'. The results of the experimental investigation are discussed with respect to the accepted understanding of the behaviour of cellulose structures. From this discussion, the implications for processing of cartonboard are identified and guidelines and considerations for storage and handling are proposed. Copyright © 2005 John Wiley & Sons, Ltd. [source] Development of a validated liquid chromatography/tandem mass spectrometry method for the distinction of thyronine and thyronamine constitutional isomers and for the identification of new deiodinase substratesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 20 2008Susanne Piehl Thyronines (THs) and thyronamines (TAMs) are two groups of endogenous iodine-containing signaling molecules whose representatives differ from each other only regarding the number and/or the position of the iodine atoms. Both groups of compounds are substrates of three deiodinase isozymes, which catalyze the sequential reductive removal of iodine from the respective precursor molecule. In this study, a novel analytical method applying liquid chromatography/tandem mass spectrometry (LC-MS/MS) was developed. This method permitted the unequivocal, simultaneous identification and quantification of all THs and TAMs in the same biological sample. Furthermore, a liquid-liquid extraction procedure permitting the concurrent isolation of all THs and TAMs from biological matrices, namely deiodinase (Dio) reaction mixtures, was established. Method validation experiments with extracted TH and TAM analytes demonstrated that the method was selective, devoid of matrix effects, sensitive, linear over a wide range of analyte concentrations and robust in terms of reproducible recoveries, process efficiencies as well as intra-assay and inter-assay stability parameters. The method was applied to study the deiodination reactions of iodinated THs catalyzed by the three deiodinase isozymes. With the HPLC protocol developed herein, sufficient chromatographic separation of all constitutional TH and TAM isomers was achieved. Accordingly, the position of each iodine atom removed from a TH substrate in a Dio-catalyzed reaction was backtracked unequivocally. While several established deiodination reactions were verified, two as yet unknown reactions, namely the phenolic ring deiodination of 3,,5,-diiodothyronine (3,,5,-T2) by Dio2 and the tyrosyl ring deiodination of 3-monoiodothyronine (3-T1) by Dio3, were newly identified. Copyright © 2008 John Wiley & Sons, Ltd. [source] Comparative analysis of efficiency, environmental impact, and process economics for mature biomass refining scenariosBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 2 2009Mark Laser Abstract Fourteen mature technology biomass refining scenarios , involving both biological and thermochemical processing with production of fuels, power, and/or animal feed protein , are compared with respect to process efficiency, environmental impact , including petroleum use, greenhouse gas (GHG) emissions, and water use,and economic profitability. The emissions analysis does not account for carbon sinks (e.g., soil carbon sequestration) or sources (e.g., forest conversion) resulting from land-use considerations. Sensitivity of the scenarios to fuel and electricity price, feedstock cost, and capital structure is also evaluated. The thermochemical scenario producing only power achieves a process efficiency of 49% (energy out as power as a percentage of feedstock energy in), 1359 kg CO2 equivalent avoided GHG emissions per Mg feedstock (current power mix basis) and a cost of $0.0575/kWh ($16/GJ), at a scale of 4535 dry Mg feedstock/day, 12% internal rate of return, 35% debt fraction, and 7% loan rate. Thermochemical scenarios producing fuels and power realize efficiencies between 55 and 64%, avoided GHG emissions between 1000 and 1179 kg/dry Mg, and costs between $0.36 and $0.57 per liter gasoline equivalent ($1.37 , $2.16 per gallon) at the same scale and financial structure. Scenarios involving biological production of ethanol with thermochemical production of fuels and/or power result in efficiencies ranging from 61 to 80%, avoided GHG emissions from 965 to 1,258 kg/dry Mg, and costs from $0.25 to $0.33 per liter gasoline equivalent ($0.96 to $1.24/gallon). Most of the biofuel scenarios offer comparable, if not lower, costs and much reduced GHG emissions (>90%) compared to petroleum-derived fuels. Scenarios producing biofuels result in GHG displacements that are comparable to those dedicated to power production (e.g., >825 kg CO2 equivalent/dry Mg biomass), especially when a future power mix less dependent upon fossil fuel is assumed. Scenarios integrating biological and thermochemical processing enable waste heat from the thermochemical process to power the biological process, resulting in higher overall process efficiencies than would otherwise be realized , efficiencies on par with petroleum-based fuels in several cases. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Comparative Study of Cyanobacteria as Biocatalysts for the Asymmetric Synthesis of Chiral Building BlocksENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 2 2006J. Havel Abstract The three representative cyanobacteria, Synechococcus PCC7942, Anabaena variabilis, and Nostoc muscorum, were studied for their ability to asymmetrically reduce the prochiral ketones 2,-3,-4,-5,-6,-pentafluoroacetophenone, ethyl 4-chloroacetate, 4-chloroacetophenone, and ethylbenzoylacetate to the corresponding chiral alcohols. Photosynthesis as well as respiration was applied for intracellular regeneration of the NAD(P)H cofactor. It was shown for the first time that all cyanobacteria were able to reduce the prochiral ketones asymmetrically without light for cofactor regeneration. By comparison of the cell specific product formation capacities of cyanobacteria with typical heterotrophic whole cell biocatalysts in batch processes, it is shown that comparable or, in some cases, better performances at high enantiomeric excess (ee > 99.8,%) are obtained. As a consequence of a generally strong product inhibition, in situ product removal must be applied in order to restore process efficiency when using cyanobacteria as biocatalysts. [source] Monitoring of Machining Processes Using Sensor Equipped Tools,ADVANCED ENGINEERING MATERIALS, Issue 7 2010Ekkard Brinksmeier A different to conventional monitoring systems sensor equipped tools give the possibility to gain information about the process status directly from the contact zone between tool and component to be machined. For example this can be realized by the integration of small temperature sensors into grinding wheels. The transmitting of the process data is performed by a telemetric unit attached to the grinding wheel's core. In this paper, the development of a new thin film thermocouple sensor concept is described. The unique feature of this sensor is the continuous contacting of the thermocouple through the grinding process inherent wear which leads to smearing of the thermoelectric layers and thus forming the measuring junction of a thermocouple. The system was used in OD grinding processes aiming to detect grinding burn and process instabilities. By reducing the volume of the sensors a fast response and high time resolution can be obtained. By this way, observance of the key parameters of the practical operation as closely as possible to the cutting area is enabled and so observance of process efficiency and tool status independent from workpiece machining conditions can be realized. All sensors used are thermocouples of type K, a combination of Chromel (NiCr) and Alumel (NiAlMnSi) material. The maximum temperature to be measured by this sensor is about 1350,°C, which ensures the applicability in the grinding process. Telemetry components to amplify and send the thermovoltage signals are adjusted to this type of thermocouple. The ability of the set-up to detect thermal influences was demonstrated in grinding processes with a continuously increasing specific material removal rate. The approach serves to measure temperatures between fast sliding surfaces in harsh environments (fluids, high pressure, heat), similar to the grinding process. Therefore their application is not limited to tools but also applicable for other rotating components such as bearings, gears and shafts in powertrains. [source] A socio-cognitive interpretation of the potential effects of downsizing on software quality performanceINFORMATION SYSTEMS JOURNAL, Issue 3 2010Paul J. Ambrose Abstract Organizational downsizing research indicates that downsizing does not always realize its strategic intent and may, in fact, have a detrimental impact on organizational performance. In this paper, we extend the notion that downsizing negatively impacts performance and argue that organizational downsizing can potentially be detrimental to software quality performance. Using social cognitive theory (SCT), we primarily interpret the negative impacts of downsizing on software quality performance by arguing that downsizing results in a realignment of social networks (environmental factors), thereby affecting the self-efficacy and outcome expectations of a software professional (personal factors), which, in turn, affect software quality performance (outcome of behaviour undertaken). We synthesize relevant literature from the software quality, SCT and downsizing research streams and develop a conceptual model. Two major impacts of downsizing are hypothesized in the conceptual model. First, downsizing destroys formal and informal social networks in organizations, which, in turn, negatively impacts software developers' self-efficacy and outcome expectations through their antecedents, with consequent negative impacts on software development process efficiency and software product quality, the two major components of software quality performance. Second, downsizing negatively affects antecedents of software development process efficiency, namely top management leadership, management infrastructure sophistication, process management efficacy and stakeholder participation with consequent negative impacts on software quality performance. This theoretically grounded discourse can help demonstrate how organizational downsizing can potentially impact software quality performance through key intervening constructs. We also discuss how downsizing and other intervening constructs can be managed to mitigate the negative impacts of downsizing on software quality performance. [source] Climate change levy and its application within the dairy industryINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2003George S Plemper The government's climate change levy on energy use in the nondomestic sector was announced in the March 1999 Budget and came into effect on 1 April 2001. During 1990 it is estimated that 603 million tonnes of carbon dioxide contributed to 79% of the UK's greenhouse gas emissions. Nationally, energy consumption within the dairy industry contributes to only 0.2% of the UK's annual emissions of carbon dioxide and climate change levy agreements throughout the industry are unlikely to have a major impact on the government's Climate Change Programme. Paradoxically, the arrangements that dairies are required to put into place as part of their Climate Change Agreements are of paramount importance for the achievement of operational and process efficiency within the dairy sector. [source] Assessment of airflow patterns inside six industrial beef carcass chillersINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2001Pierre-Sylvain Mirade Airflow patterns determine process efficiency in beef carcass chilling. An experimental study of air velocity in six industrial chillers (three batch and three continuous systems) afforded a diagnosis of their overall operation. However, the original experimental method did not provide an ideal chiller design: only configurations that were a priori more favourable for carcass chilling than others were identified. To complete the study, calculations were performed using computational fluid dynamics techniques. Applied to a continuous beef carcass chiller, this helped correct a dysfunction revealed in the experimental diagnosis, resulting in a marked lack of ventilation throughout about half the volume of the plant. [source] OUTSIDE UPSIDE: FINDINGS FOCUS THROUGH FINANCE OUTSOURCINGJOURNAL OF APPLIED CORPORATE FINANCE, Issue 4 2003Stewart Clements More and more companies are outsourcing aspects of the finance and accounting function to cut costs and increase process efficiency. This article draws on survey results and numerous real-world examples to make the case for outsourcing finance and accounting functions, either outright or through shared service centers. As expected, cost and efficiency gains can be dramatic. But there are also important strategic benefits, including the freedom to focus on core businesses, greater access to specialist knowledge, standardization of processes across business units, and the ability to launch operations quickly without staffing back offices. Maximizing the benefits of outsourcing requires careful planning and execution. Executives who have successfully navigated the process recommend allowing adequate time to ensure buy-in and consensus building, incorporating the appropriate performance-based incentives, taking steps to build morale during the transition, ensuring proper oversight, and building a strong partnership with the provider. When properly implemented, outsourcing is a powerful ally in the corporate struggle to cut costs,and it can be a vital complement to strategy as well. [source] Silicone oil: An effective absorbent for the removal of hydrophobic volatile organic compoundsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 3 2010Guillaume Darracq Abstract BACKGROUND: Hydrophobic volatile organic compounds (VOCs), such as toluene, dimethyl sulfide (DMS) and dimethyl disulfide (DMDS), are poorly soluble in water and classical air treatment processes like chemical scrubbers are not efficient. An alternative technique involving an absorption step in an organic solvent followed by a biodegradation phase was proposed. The solvent must fulfil several characteristics, which are key factors of process efficiency, and a previous study allowed polydimethylsiloxane (or PDMS, i.e. silicone oil) to be selected for this purpose. The aim of this paper was to determine some of its characteristics like absorption capacity and velocity performances (Henry's constant, diffusivity and mass transfer coefficient), and to verify its non-biodegradability. RESULTS: For the three targeted VOCs, Henry's constants in silicone oil were very low compared to those in water, and solubility was infinite. Diffusivity values were found to be in the range 10,10 to 10,11 m2 s,1 and mass transfer coefficients did not show significant differences between the values in pure water and pure silicone oil, in the range 1.0 × 10,3 to 4.0 × 10,3 s,1 for all the VOCs considered. Silicone oil was also found to be non-biodegradable, since its biological oxygen demand (BOD5) value was zero. CONCLUSION: Absorption performances of silicone oil towards toluene, DMS and DMDS were determined and showed that this solvent could be used during the first step of the process. Moreover, its low biodegradability and its absence of toxicity justify its use as an absorbent phase for the integrated process being considered. Copyright © 2010 Society of Chemical Industry [source] Cell-free ethanol production: the future of fuel ethanol?JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2007Eric J. Allain Abstract The production of fuel ethanol from renewable resources as an economically viable alternative to gasoline is currently the subject of much research. Most studies seek to improve process efficiency by increasing the rate of ethanol production; ultimately, this approach will be limited by the selected ethanol-producing microorganism. Cell-free ethanol production, using only the enzymes involved in the conversion of glucose to ethanol, may offer a practical and beneficial alternative. Mathematical modeling of such a system has suggested that a cell-free process should be capable of producing ethanol much more efficiently than the microbial based process. This finding along with other potential benefits of a microorganism-free process suggests that a cell-free process might significantly improve the economy of fuel ethanol production and is a worthy target for further research. Copyright © 2007 Society of Chemical Industry [source] Enantioseparation via EIC-OSN: Process design and improvement of enantiomers resolvability and separation performanceAICHE JOURNAL, Issue 4 2010Issara Sereewatthanawut Abstract This article presents a mathematical model to assess and optimize the separation performance of an enantioselective inclusion complexation-organic solvent nanofiltration process. Enantiomer solubilities, feed concentrations, solvent compositions, permeate solvent volumes, and numbers of nanofiltrations were identified as key factors for process efficiency. The model was first tested by comparing calculated and experimental results for a nonoptimized process, and then, calculations were carried out to select the best operating conditions. An important finding was that the optimal configuration varied with the objective function selected, e.g., resolvability versus yield, with a boundary on product optical purity. The model also suggested that the process efficiency could benefit from diafiltration of the distomer and from the use of higher feed concentrations. However, the latter strategy would result in higher losses of eutomer. To address this drawback, a multistage process was evaluated using the verified process model. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Nanoscopic characterization of a plastisol gelation and fusion process utilizing scanning electron microscopy and atomic force microscopyJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 3 2008Jerome S. Jourdan Understanding the physical properties associated with the gelation and fusion of a PVC plastisol will help to improve process efficiency. Plastisol gelation and fusion were characterized by using both scanning electron microscopy (SEM) and atomic force microscopy (AFM) and were compared with the tensile properties developed at various temperatures. Both SEM and AFM showed good agreement during the early stages of gelation. However, AFM continued to show particle boundaries during the latter stages of gelation and fusion that provided a more nearly accurate comparison with the resulting tensile properties. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers. [source] Engineering photosynthetic light capture: impacts on improved solar energy to biomass conversionPLANT BIOTECHNOLOGY JOURNAL, Issue 6 2007Jan H. Mussgnug Summary The main function of the photosynthetic process is to capture solar energy and to store it in the form of chemical ,fuels'. Increasingly, the photosynthetic machinery is being used for the production of biofuels such as bio-ethanol, biodiesel and bio-H2. Fuel production efficiency is directly dependent on the solar photon capture and conversion efficiency of the system. Green algae (e.g. Chlamydomonas reinhardtii) have evolved genetic strategies to assemble large light-harvesting antenna complexes (LHC) to maximize light capture under low-light conditions, with the downside that under high solar irradiance, most of the absorbed photons are wasted as fluorescence and heat to protect against photodamage. This limits the production process efficiency of mass culture. We applied RNAi technology to down-regulate the entire LHC gene family simultaneously to reduce energy losses by fluorescence and heat. The mutant Stm3LR3 had significantly reduced levels of LHCI and LHCII mRNAs and proteins while chlorophyll and pigment synthesis was functional. The grana were markedly less tightly stacked, consistent with the role of LHCII. Stm3LR3 also exhibited reduced levels of fluorescence, a higher photosynthetic quantum yield and a reduced sensitivity to photoinhibition, resulting in an increased efficiency of cell cultivation under elevated light conditions. Collectively, these properties offer three advantages in terms of algal bioreactor efficiency under natural high-light levels: (i) reduced fluorescence and LHC-dependent heat losses and thus increased photosynthetic efficiencies under high-light conditions; (ii) improved light penetration properties; and (iii) potentially reduced risk of oxidative photodamage of PSII. [source] Flow modeling and simulation for vacuum assisted resin transfer molding process with the equivalent permeability methodPOLYMER COMPOSITES, Issue 2 2004Renliang Chen Vacuum assisted resin transfer molding (VARTM) offers numerous advantages over traditional resin transfer molding, such as lower tooling costs, shorter mold filling time and better scalability for large structures. In the VARTM process, complete filling of the mold with adequate wet-out of the fibrous preform has a critical impact on the process efficiency and product quality. Simulation is a powerful tool for understanding the resin flow in the VARTM process. However, conventional three-dimensional Control Volume/Finite Element Method (CV/FEM) based simulation models often require extensive computations, and their application to process modeling of large part fabrication is limited. This paper introduces a new approach to model the flow in the VARTM process based on the concept of equivalent permeability to significantly reduce computation time for VARTM flow simulation of large parts. The equivalent permeability model of high permeable medium (HPM) proposed in the study can significantly increase convergence efficiency of simulation by properly adjusting the aspect ratio of HPM elements. The equivalent permeability model of flow channel can simplify the computational model of the CV/FEM simulation for VARTM processes. This new modeling technique was validated by the results from conventional 3D computational methods and experiments. The model was further validated with a case study of an automobile hood component fabrication. The flow simulation results of the equivalent permeability models were in agreement with those from experiments. The results indicate that the computational time required by this new approach was greatly reduced compared to that by the conventional 3D CV/FEM simulation model, while maintaining the accuracy, of filling time and flow pattern. This approach makes the flow simulation of large VARTM parts with 3D CV/FEM method computationally feasible and may help broaden the application base of the process simulation. Polym. Compos. 25:146,164, 2004. © 2004 Society of Plastics Engineers. [source] Real-time monitoring of injection molding for microfluidic devices using ultrasoundPOLYMER ENGINEERING & SCIENCE, Issue 4 2005Y. Ono Real-time process monitoring of the fabrication process of microfluidic devices using a polymer injection molding machine was carried out using miniature ultrasonic probes. A thick piezoelectric lead-zirconate-titanate film as an ultrasonic transducer (UT) was fabricated onto one end of a 4-mm diameter and 12-mm long steel buffer rods using a sol gel spray technique. The center frequency and 6 dB bandwidth of this UT were 17 MHz and 14 MHz, respectively. A signal-to-noise ratio of more than 30 dB for ultrasonic signals reflected at the probing end was achieved. The probe can operate continuously at 200°C without ultrasonic couplant and cooling. Clear ultrasonic signals were obtained during injection molding of a 1-mm-thick part having test patterns on its surface. Shrinkage of the molded part and part detachment from the mold were successfully monitored. Surface imperfections of the molded parts due to a lack of the sufficient holding pressure is discussed with regard to the ultrasonic velocity obtained. The presented ultrasonic probes and technique enable on-line quality control of the molded part by optimizing the holding pressure and improvement of process efficiency by reducing the cycle time. POLYM. ENG. SCI., 45:606,612, 2005. © 2005 Society of Plastics Engineers [source] Coproduction of ethanol and power from switchgrassBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 2 2009Mark Laser Abstract Three process designs for producing ethanol and electricity from switchgrass are evaluated: a base-case technology scenario involving dilute acid pre-treatment and simultaneous saccharification and fermentation, and two mature technology scenarios incorporating ammonia fiber expansion pre-treatment and consolidated bioprocessing , one with conventional Rankine power coproduction, and one coproducing power via a gas turbine combined cycle. Material and energy balances , resulting from detailed Aspen Plus models , are reported and used to estimate processing costs and perform discounted cash flow analysis to assess plant profitability. The mature technology ,designs significantly improve both process efficiency and cost relative to base-case cellulosic ethanol technology, with the resulting fossil fuel displacement being decidedly positive and production costs competitive with gasoline, even at relatively low prices. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Comparative analysis of efficiency, environmental impact, and process economics for mature biomass refining scenariosBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 2 2009Mark Laser Abstract Fourteen mature technology biomass refining scenarios , involving both biological and thermochemical processing with production of fuels, power, and/or animal feed protein , are compared with respect to process efficiency, environmental impact , including petroleum use, greenhouse gas (GHG) emissions, and water use,and economic profitability. The emissions analysis does not account for carbon sinks (e.g., soil carbon sequestration) or sources (e.g., forest conversion) resulting from land-use considerations. Sensitivity of the scenarios to fuel and electricity price, feedstock cost, and capital structure is also evaluated. The thermochemical scenario producing only power achieves a process efficiency of 49% (energy out as power as a percentage of feedstock energy in), 1359 kg CO2 equivalent avoided GHG emissions per Mg feedstock (current power mix basis) and a cost of $0.0575/kWh ($16/GJ), at a scale of 4535 dry Mg feedstock/day, 12% internal rate of return, 35% debt fraction, and 7% loan rate. Thermochemical scenarios producing fuels and power realize efficiencies between 55 and 64%, avoided GHG emissions between 1000 and 1179 kg/dry Mg, and costs between $0.36 and $0.57 per liter gasoline equivalent ($1.37 , $2.16 per gallon) at the same scale and financial structure. Scenarios involving biological production of ethanol with thermochemical production of fuels and/or power result in efficiencies ranging from 61 to 80%, avoided GHG emissions from 965 to 1,258 kg/dry Mg, and costs from $0.25 to $0.33 per liter gasoline equivalent ($0.96 to $1.24/gallon). Most of the biofuel scenarios offer comparable, if not lower, costs and much reduced GHG emissions (>90%) compared to petroleum-derived fuels. Scenarios producing biofuels result in GHG displacements that are comparable to those dedicated to power production (e.g., >825 kg CO2 equivalent/dry Mg biomass), especially when a future power mix less dependent upon fossil fuel is assumed. Scenarios integrating biological and thermochemical processing enable waste heat from the thermochemical process to power the biological process, resulting in higher overall process efficiencies than would otherwise be realized , efficiencies on par with petroleum-based fuels in several cases. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Optimization of chimeric HIV-1 virus-like particle production in a baculovirus-insect cell expression systemBIOTECHNOLOGY PROGRESS, Issue 4 2009Sirika Pillay Abstract A baculovirus-insect cell expression system potentially provides the means to produce prophylactic HIV-1 virus-like particle (VLP) vaccines inexpensively and in large quantities. However, the system must be optimized to maximize yields and increase process efficiency. In this study, we optimized the production of two novel, chimeric HIV-1 VLP vaccine candidates (GagRT and GagTN) in insect cells. This was done by monitoring the effects of four specific factors on VLP expression: these were insect cell line, cell density, multiplicity of infection (MOI), and infection time. The use of western blots, Gag p24 ELISA, and four-factorial ANOVA allowed the determination of the most favorable conditions for chimeric VLP production, as well as which factors affected VLP expression most significantly. Both VLP vaccine candidates favored similar optimal conditions, demonstrating higher yields of VLPs when produced in the Trichoplusia ni ProÔ insect cell line, at a cell density of 1 × 106 cells/mL, and an infection time of 96 h post infection. It was found that cell density and infection time were major influencing factors, but that MOI did not affect VLP expression significantly. This work provides a potentially valuable guideline for HIV-1 protein vaccine optimization, as well as for general optimization of a baculovirus-based expression system to produce complex recombinant proteins. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Oxidative Degradation of Azo Dyes by Manganese Peroxidase under Optimized ConditionsBIOTECHNOLOGY PROGRESS, Issue 2 2003I. Mielgo The application of enzyme-based systems in waste treatment is unusual, given that many drawbacks are derived from their use, including low efficiency, high costs and easy deactivation of the enzyme. The goal of this study is the development of a degradation system based on the use of the ligninolytic enzyme manganese peroxidase (MnP) for the degradation of azo dyes. The experimental work also includes the optimization of the process, with the objective of determining the influence of specific physicochemical factors, such as organic acids, H2O2 addition, Mn2+ concentration, pH, temperature, enzyme activity and dye concentration. A nearly total decolorization was possible at very low reaction times (10 min) and at high dye concentration (up to 1500 mg L,1). A specific oxidation capacity as high as 10 mg dye degraded per unit of MnP consumed was attained for a decolorization higher than 90%. Among all, the main factor affecting process efficiency was the strategy of H2O2 addition. The continuous addition at a controlled flow permitted the progressive participation of H2O2 in the catalytic cycle through a suitable regeneration of the oxidized form of the enzyme, which enhanced both the extent and the rate of decolorization. It was also found that, in this particular case, the presence of a chelating organic acid (e.g., malonic) was not required for an effective operation. Probably, Mn3+ was chelated by the dye itself. The simplicity and high efficiency of the process open an interesting possibility of using of MnP for solving other environmental problems. [source] A factorially-designed study of physicochemical reactive dye colour removal from simulated cotton textile processing wastewatersCOLORATION TECHNOLOGY, Issue 5 2002G Carvalho The process performance of coagulation to remove reactive dyes from dyehouse effluent is affected by multiple factors, which can be best examined in factorially-designed experiments. A preliminary jar-test procedure was used to select coagulants and the optimal pH and coagulant dosage ranges. An inorganic salt (ferrous sulphate) and an organic polymer (DEC 50) were selected for further studies. Factorially-designed jar-test experiments were performed with different compositions of a synthetic cotton processing wastewater to determine which factors most affected colour removal and highlight interactions between them. Some additives, such as an oxidative desizing agent and a peroxide stabiliser, favoured colour removal within specific concentration ranges. The presence of sizing agents and surfactants reduced process efficiency. Increasing concentrations of ferrous sulphate could counteract this, but would result in higher sludge disposal costs. [source] | |||||||||||||||||||||||||||||||